-76.66% is the change from 664 to 155
Calculation steps:
[( 155 - 664 ) ÷ 664] x 100 = -76.66%
Formula
Percentage change = [(155 - 664) / 664] x 100
Subtract the new number by the original number
155 - 664 = -509
-509 ÷ 664 = -0.766566265060241
-0.766566265060241 x 100 = -76.66%